AERIX CPU Open calculator
Browser-based · No install

CPU Temperature
Calculator

Estimate CPU temperatures based on your processor, cooler, case airflow and fan setup.

Open Aerix Calculator How it works

Fast engineering estimate — not a CFD simulation.

Overview

What affects CPU temperature?

Your CPU temperature is not set by the cooler alone. It depends on how much power the processor draws, how well the cooler can move that heat away, and whether the cooler is actually getting fresh air from the case.

Processor power (TDP / power limit)
CPU cooler class and size
Air reaching the CPU socket
Case intake and exhaust layout
Ambient room temperature
Air vs. AIO liquid cooling
Workflow

How Aerix estimates CPU temperature

Aerix estimates CPU temperature using your processor power, CPU cooler performance, case airflow and fan configuration. Instead of relying only on manufacturer specifications, Aerix models how your complete PC build affects cooling performance.

1

Enter your build

Select your case, CPU cooler, GPU, fan layout and approximate CPU power.

2

Compare cooling setups

Swap the cooler, change fan direction or add fans and watch the estimated CPU temperature react.

3

Get a CPU estimate

Aerix returns an estimated CPU temperature and shows whether the build looks airflow-limited or cooler-limited.

Worked example

Fan direction can cool the CPU

A change that barely touches the GPU can noticeably help the CPU — because the CPU cooler is far more sensitive to whether it receives fresh intake air.

The build

CaseLian Li A3-mATX
CPU coolerPeerless Assassin 120
GPURTX 4070 SUPER
Bottom intake2 fans
Rear exhaust1 fan
Top fans2 fans
Scenario A Top exhaust
CPU77°C
GPU70°C
Scenario B Top intake
CPU71°C
GPU70°C

Switching the top fans to intake drops the estimated CPU temperature by -6°C while the GPU stays at 70°C. The CPU cooler simply had more fresh air to work with — fan direction, not a bigger cooler.

Try this build in Aerix

Questions

Frequently asked

What is a safe CPU temperature?
Most modern desktop CPUs run comfortably under load in the roughly 60–85°C range and will throttle to protect themselves near their limit. Lower is quieter and leaves more headroom, but a warm CPU under full load is not automatically a problem.
Does the CPU cooler alone decide my temperature?
No. The cooler sets the ceiling of what is possible, but processor power draw, case airflow, ambient temperature and mounting quality all move the final number. A strong cooler starved of fresh air can still run hot.
Does case airflow really affect CPU temperature?
Yes. The cooler can only reject heat into the air it is given. If the case cannot supply cool intake air to the socket area, the CPU runs hotter even with a large cooler installed.
Is an AIO always cooler than an air cooler?
Not necessarily. A good dual-tower air cooler can match or beat an entry-level AIO. AIOs help most with high-power CPUs and let you move heat straight to a radiator, but they add pump noise and cost.
Why is my real CPU temperature higher than the Aerix estimate?
Common causes are old or poorly applied thermal paste, imperfect cooler contact, dust buildup, restrictive panels, incorrect fan direction or aggressive boost behavior that pushes more power than expected.
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Estimate your build in the browser

Pick your case, cooler, GPU and fans — then compare cooling scenarios side by side.

Open Aerix Calculator